title: The value of laboratory tests in diagnosing secondary osteoporosis at a fracture and osteoporosis outpatient clinic.
abstract: BACKGROUND
  As more and more patients meeting the criteria for osteoporosis are referred to a fracture and osteoporosis outpatient clinic (FO clinic), the laboratory costs to screen for secondary osteoporosis also increases. This study was conducted to determine the value of screening on underlying diseases at an FO clinic by obtaining a standard set of laboratory tests.
  
  
  METHODS
  We included all 541 patients ≥50 years with a fracture referred to our FO clinic, during the period January 2005 to January 2007. The bone mineral density (BMD) was measured by dual energy x-ray absorptiometry and expressed as a T score. A standard set of laboratory tests was obtained to screen on underlying diseases.
  
  
  RESULTS
  Laboratory results were as often abnormal in patients with a normal BMD compared to patients with a low BMD. Underlying diseases were infrequently diagnosed. However, the prevalence of secondary osteoporosis in men was quite high, up to 18.2%. The costs to diagnose 1 patient with an underlying disease did vary between €92 and €972 depending on the group of patients described.
  
  
  CONCLUSIONS
  Screening all patients, referred to an FO clinic, for underlying diseases by obtaining a standard set of laboratory tests is probably not useful since laboratory tests are as often abnormal in patients with a normal BMD compared to patients with a low BMD. Moreover, the prevalence of secondary osteoporosis is low, while laboratory costs are substantial.
authors.affiliation: Department of Surgery, Ziekenhuisgroep Twente, Almelo, the Netherlands.
authors.forename: Gijs
authors.initials: G
authors.lastname: de Klerk
authors.forename: J Han
authors.initials: JH
authors.lastname: Hegeman
authors.forename: Detlef
authors.initials: D
authors.lastname: van der Velde
authors.forename: Job
authors.initials: J
authors.lastname: van der Palen
authors.forename: Leo
authors.initials: L
authors.lastname: van Bergeijk
authors.forename: Henk J Ten
authors.initials: HJ
authors.lastname: Duis
keywords: dual energy x-ray absorptiometry; fracture and osteoporosis outpatient clinic; osteoporosis; secondary osteoporosis; trauma surgery